The Collaborative International Dictionary of English v.0.48:

Roller \Roll"er\ (r[=o]l"[~e]r), n.
   1. One who, or that which, rolls; especially, a cylinder,
      sometimes grooved, of wood, stone, metal, etc., used in
      husbandry and the arts.
      [1913 Webster]

   2. A bandage; a fillet; properly, a long and broad bandage
      used in surgery.
      [1913 Webster]

   3. (Naut.) One of series of long, heavy waves which roll in
      upon a coast, sometimes in calm weather.
      [1913 Webster]

   4. A long, belt-formed towel, to be suspended on a rolling
      cylinder; -- called also roller towel.
      [1913 Webster]

   5. (Print.) A cylinder coated with a composition made
      principally of glue and molassess, with which forms of
      type are inked previously to taking an impression from
      them. --W. Savage.
      [1913 Webster]

   6. A long cylinder on which something is rolled up; as, the
      roller of a map.
      [1913 Webster]

   7. A small wheel, as of a caster, a roller skate, etc.
      [1913 Webster]

   8. (Zool.) Any insect whose larva rolls up leaves; a leaf
      roller. see Tortrix.
      [1913 Webster]

   9. [CF. F. rollier.] (Zool.) Any one of numerous species of
      Old World picarian birds of the family Coraciadae. The
      name alludes to their habit of suddenly turning over or
      "tumbling" in flight.
      [1913 Webster]

   Note: Many of the species are brilliantly colored. The common
         European species (Coracias garrula) has the head,
         neck, and under parts light blue varied with green, the
         scapulars chestnut brown, and the tail blue, green, and
         black. The broad-billed rollers of India and Africa
         belong to the genus Eurystomus, as the oriental
         roller (Eurystomus orientalis), and the Australian
         roller, or dollar bird (Eurystomus Pacificus). The
         latter is dark brown on the head and neck, sea green on
         the back, and bright blue on the throat, base of the
         tail, and parts of the wings. It has a silvery-white
         spot on the middle of each wing. The lilac-breasted
         roller of Africa is Corcia caudata caudata, a
         brightly colored bird of the family Corciidae having
         malachite green, blue, purple-lilac, brown and
         sea-green feathers from head to tail; it is a popular
         sight with tourists in Africa.
         [1913 Webster +PJC]

WordNet (r) 3.0 (2006):

roller
    n 1: a grounder that rolls along the infield
    2: a long heavy sea wave as it advances towards the shore [syn:
       roller, roll, rolling wave]
    3: a small wheel without spokes (as on a roller skate)
    4: a cylinder that revolves
    5: a mechanical device consisting of a cylindrical tube around
       which the hair is wound to curl it; "a woman with her head
       full of curlers is not a pretty sight" [syn: curler, hair
       curler, roller, crimper]
    6: Old World bird that tumbles or rolls in flight; related to
       kingfishers
    7: pigeon that executes backward somersaults in flight or on the
       ground [syn: roller, tumbler, tumbler pigeon]

Moby Thesaurus II by Grady Ward, 1.0:

137 Moby Thesaurus words for "roller":
   Ace bandage, Band-Aid, abradant, abrasive, adhesive tape,
   application, band, bandage, bandaging, barrel, billow, binder,
   bole, bore, brace, breaker, breakers, burnish, calender, carousel,
   cask, cast, cataplasm, cheese grater, chop, choppiness,
   chopping sea, column, comb, comber, comminutor, compress, cotton,
   court plaster, cravat, crusher, cylinder, cylindroid, dirty water,
   disk, dressing, drum, eagre, elastic bandage, epithem,
   four-tailed bandage, gauze, granulator, grater, gravity wave,
   grinder, ground swell, heave, heavy sea, heavy swell, kominuter,
   lawn-roller, levigator, lift, lint, lop, mangle, masher,
   merry-go-round, mill, millstone, mortar and pestle, nutmeg grater,
   peak, pestle, pillar, pipe, plaster, plaster cast, pledget, polish,
   popple, poultice, pulverizer, quern, quernstone, riffle, ripple,
   rise, rock crusher, roll, roller bandage, rolling stone, rotator,
   rotor, rough water, rouleau, roundabout, rubber bandage, rundle,
   scend, sea, send, shredder, sleeker, slicker, sling, smooth,
   smoother, splint, sponge, steamroller, stupe, surf, surge, swell,
   tampon, tape, tent, tidal bore, tidal wave, tide wave, top,
   tourniquet, triangular bandage, triturator, trough, trunk, tsunami,
   tube, undulation, water wave, wave, wavelet, wheel, whirlabout,
   whirler, whirligig, white horses, whitecaps, windlass, wringer